In solar-terrestrial terms, a daily average background X-ray flux in the 1 to 8
angstrom range. It is a midday minimum designed to reduce the
effects of flares.

X-Ray Burst

In solar-terrestrial terms, a temporary enhancement of the X-ray emission of the sun. The
time-intensity profile of soft X-ray bursts is similar to that of
the H-alpha profile of an associated flare.

X-Ray Flare Class

In solar-terrestrial terms, rank of a flare based on its X-ray energy output. Flares are classified by the order of magnitude of the peak burst intensity (I) measured at the earth in the 1 to 8 angstrom band as follows:

Class

Intensity (in Watts/m2)

B

I < 10-6

C

10-6 <= I < 10-5

M

10-5 <= I < 10-4

X

I >= 10-4

X-Rays

Very energetic electromagnetic radiation with wavelengths intermediate between 0.01 and 10 nanometers (0.1-100 Angstroms) or between gamma rays and ultraviolet radiation. Essentially all X-Rays from space are absorbed in the Earth's upper atmosphere.

XBT

Expendable Bathythermograph

XCITED

Excited

XCPT

Expecting

XPC

Expect

XSEC

Cross Section

You can either type in the word you are looking for in the box below or browse by letter.